1. Technical Field
The present invention relates generally to apparatus for cutting segments of wire or cable from a supply of such wire or cable, and, more particularly to apparatus which collect the wire or cable segments discharged from such wire and cable cutting apparatus.
2. Background Art
With the advent of automated machinery, wire and cable cutting machines were developed and successfully employed to produce a wide variety of wire and cable products. Such machines operate on a supply of wire or cable (e.g., a reel or continuous feed strand) and cut relatively short segments from this supply for further processing and assembly. An obvious problem presented by such automated machines is how to handle or collect the segments as they are discharged from such machines. Some of these machines can operate at relatively high rates of speed (i.e., high cycle rates), producing 20-30 segments of wire or cable per minute. The problem of handing such demanding outputs has been long-standing, and, heretofore, has not been adequately addressed in the art.
Conventional approaches to collection or handling of wire segments from cutting machines have included--collection hangers, trays, troughs or tubes; conveyer belt systems; and coiling pans or baskets. For example, U.S. Pat. No. 4,502,586 to Dusel et al. discloses a conveyer belt for conveying wire segments, and U.S. Pat. No. 4,266,455 to Ago discloses a conveyer belt and collection tray arrangement.
The disadvantage with simply using collection trays, troughs, etc., is that the wire segments (especially if longer than 2-3 feet) usually become entangled in these collectors. Such entanglements preclude further processing of these segments until they are untangled--usually by a manual operator. This severely slows the manufacturing process of wire or cable products. The entanglement problem is especially acute when such collectors are intended to retrieve a large number of segments (e.g., 1,000 pieces). Thus, such collector devices are limited to small output applications and short segment lengths.
Conveyer belt systems are usually employed when it is desired to fully automate the processing of the segments from supply strand to finished product (e.g., electrical extension cord). After the segments are cut, they are conveyed by conveyer belt to the next station for further processing. One disadvantage of conveyer belt systems is that they are usually designed for a particular application, involving a narrow range of segment lengths and discharge rates. They are generally not flexible enough to handle a wide range of segment lengths and discharge rates. In addition, such systems require relatively low discharge rates for proper handling of the segments. Moreover, such systems are expensive and require a relatively high degree of maintenance.
Coiling pans are only suitable for coiled pieces. They can only collect one piece at-a-time, usually requiring manual removal of each piece on each cutting cycle of the cutting machine. Such manual intervention severely limits the rate at which the machine can be set to discharge the segments. Moreover, such devices are only suitable for segment lengths in the narrow range of 2-6 feet.
Attempts have been made to devise a collection channel in which a wire or cable portion is inserted either after or before being cut by the cutting machine. The collection channel acts to stabilize the wire or cable portion before it is directed to (e.g., dropped into) a collector, such as a tray, trough, etc. By stabilizing the wire or cable portion first, the portion (after being cut) can be neatly arranged in the collector, and entanglements can be minimized. An example of such a collection channel is shown in U.S. Pat. No. 4,158,976 to Ditges.
In Ditges, a wire segment is feed into a wire channel 23 (FIG. 5) and then cut from the main strand in the cutting machine. The segment is then dropped out of the channel when a closure 34 is opened (FIG. 5). The segment is then collected by an array of bracket-like collectors 45 (FIG. 8). While achieving the advantages of stabilizing the wire segment before collection, the Ditges design is limited because of its closed channel (i.e., the distal end is closed--See FIGS. 1 and 2). In fact, stops 17 are inserted into the channel to stop the wire segment (See FIG. 2).
Obvious drawbacks of this design include--(1) the closed end or stop can blunt or deform the terminus of the wire segment, which is very undesirable for many applications; and (2) the channel imposes a limit on the segment length that can be collected therein. To overcome the latter drawback, Ditges suggests that the channel be made modular, so that the channel can be extended by adding on modules 20 (FIG. 3). This approach adds to the expense of the wire channel. Moreover, channel reconfiguration (to adjust channel length) requires operator intervention, is time consuming, and inconvenient.
Another example of a wire channel at the output of a wire cutting machine is shown in U.S. Pat. No. 4,493,233 to Dusel et al. (FIGS. 10-16). In Dusel et al., a wire channel 190 receives a wire portion through a proximal opened end and allows the terminus of the wire portion to extend through a distal opened end (FIG. 10). The wire portion is metered into the channel, and the channel is opened prior to the cutting operation (FIG. 11). Unlike Ditges, the wire portion in Dusel et al. is stabilized outside the channel just before cutting and collection by a conveyer belt (FIG. 12). This approach limits the speed at which wire segments can be collected in an orderly fashion.
In a further example, the inventors named herein developed a wire collection apparatus (referred to as the WC1000.TM.) having a tubular wire collection channel and a closure for opening and closing the wire collection channel. The closure was also a tubular channel and was positioned inside of and in concentric relation to the wire collection channel. Both the collection channel and closure contained elongated axial openings (or slots) The closure was rotatable inside the collection channel. When the axial openings of the channel and closure were in alignment, the channel was opened. When they were out of alignment, the channel was closed except for about six inches near the distal end of the collection channel. The axial slot of the closure is widened near the distal end of the collection channel, so that it does not fully close the axial slot of the collection channel at this location. The result is an elongated pening through the collection channel, about six inches long, which allows the terminal end of a wire segment to be discharged before the closure opens the channel. A deflector, located inside the closure, deflects the terminus end of the wire segment down through the elongated opening. The closure was actuated by a pneumatic actuator located at the distal end of the channel. The actuator blocked the distal end of the collection channel, preventing wire portions from extending through the distal end of the channel.
The WC1000 design required two width dimensions in the axial slot of the closure and required a deflector. Both features added to the complexity and manufacturing cost of the machine. In addition, the actuator rotated the closure tube from one end, creating an undesirable torque on the tube. This torque created imbalances which resulted in uneven wear and increased operating noise.